Light sources that emit repetitive subnanosecond pulses are used in neutrino telescopes for time calibration. Optical pulses with an ultra-narrow (subnanosecond) width can replicate the light ...produced by neutrino interactions, and are an important calibration and test element. By measuring the time-of-flight of the light, it is possible to provide a relative time calibration for all the detector photomultipliers. This work presents the UNTOPEL, an instrument emitting ultra-short laser optical pulses with a duration of 500 ps, energies per pulse of four microjoules at a wavelength of 532 nm, and a timing precision of 400 ps. The UNTOPEL pulse intensity can be fine-tuned, which is a novelty and a significant advantage in those applications that need to illuminate light detectors located at different distances with the same light intensity. The UNTOPEL pulse intensity can be controlled remotely, allowing for its use in operating conditions where physical access is impossible or difficult. Moreover, it is easy to operate and can be easily controlled through an Inter-Integrated Circuit bus. The UNTOPEL is a sound instrument when subnanosecond pulses and variable energy emissions are needed.
The High Altitude Water Cherenkov (HAWC) Observatory is a TeV gamma-ray detector located at an altitude of 4100 meters on the northern slope of the Sierra Negra volcano in the state of Puebla, ...Mexico. The detector will consist of 300 water Cherenkov detectors spread on a 22,000 square meter area, and is expected to be fully constructed by the end of 2014. Thanks to its large field-of-view, good angular resolution and >90% duty cycle, HAWC will allow us to study the Galactic sources at high energies (100 GeV – 100 TeV), diffuse gamma-ray emission, and transient emissions from active galactic nuclei and gamma-ray bursts. The detector started its continuous operation in August 2013 with a fraction of the array, and its size has been increasing since then. The first results of the experiment, with almost one year of data from the partial array, are reviewed in this proceedings.
This paper encapsulates details of the NEMO laser beacon’s design, offering a profound contribution to the field of the time calibration of underwater neutrino telescopes. The mechanical design of ...the laser beacon, which operates at a depth of 3500 m, is presented, together with the design of the antibiofouling system employed to endure the operational pressure and optimize the operational range, enhancing its functionality and enabling time calibration among multiple towers. A noteworthy innovation central to this development lies in the battery system. This configuration enhances the device’s portability, a crucial aspect in underwater operations. The comprehensive design of the laser beacon, encompassing the container housing, the requisite battery system for operation, electronics, and an effective antibiofouling system, is described in this paper. Additionally, this paper presents the findings of the laser beacon’s qualification process.
Multimessenger astronomy is arguably the branch of the astroparticle physics field that has seen the most significant developments in recent years. In this manuscript, we will review the ...state-of-the-art, the recent observations, and the prospects and challenges for the near future. We will give special emphasis to the observation carried out with neutrino telescopes.
Light sources emitting short pulses are needed in many particle physics experiments using optical sensors as they can replicate the light produced by the particles being detected and are also an ...important calibration and test element. This work presents NOPELED, a light source based on LEDs emitting short optical pulses with typical rise times of less than 3 ns and Full Width at Half Maximum lower than 7 ns. The emission wavelength depends on the model of LED used. Several LED models have been characterized in the range from 405 to 532 nm, although NOPELED can work with LED emitting wavelengths outside of that region. While the wavelength is fixed for a given LED model, the intensity and the frequency of the optical pulse can be controlled. NOPELED, which also has low cost and simple operation, can be operated remotely, making it appropriate for either different physics experiments needing in-place light sources such as astrophysical neutrino detectors using photo-multipliers or positron emission tomography devices using scintillation counters, or, beyond physics, applications needing short pulses of light such as protein fluorescence or chemodetection of heavy metals.
TeV Diffuse Emission From the Inner Galaxy Nayerhoda, Amid; Salesa Greus, Francisco; Casanova, Sabrina
Frontiers in astronomy and space sciences,
04/2018, Letnik:
5
Journal Article
Recenzirano
Odprti dostop
The TeV diffuse emission from the Galactic plane is produced by multi TeV electrons and nuclei interacting with radiation fields and ambient gas, respectively. Measurements of the TeV diffuse ...emission help constrain CR origin and transport properties. We present a preliminary analysis of HAWC diffuse emission data from the inner Galaxy. The HAWC measurements will be used to constrain particle transport properties close to the Galaxy center correlating the HAWC maps with predictions of the DRAGON code.
Nearby electron/positron accelerators, mostly Pulsar Wind Nebulae (PWNe), have been pro- posed as potential origins of the positron excess above 10 GeV. The HAWC Observatory reveals two very extended ...sources spatially coincident with two nearby middle-aged pulsars: Geminga and PSR B0656+14, suggesting ultra-relativistic electrons/positrons accelerated in our backyard. Morphological studies on these two PWNe provide a constraint on the diffusion coefficient at HAWC energies. In this poster, we will present the model development and morphological studies on these PWNe, and the derived diffusion coefficient that best fits the data.
Science with Neutrino Telescopes in Spain Hernández-Rey, Juan José; Ardid, Miguel; Bou Cabo, Manuel ...
Universe (Basel),
02/2022, Letnik:
8, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The primary scientific goal of neutrino telescopes is the detection and study of cosmic neutrino signals. However, the range of physics topics that these instruments can tackle is exceedingly wide ...and diverse. Neutrinos coming from outside the Earth, in association with other messengers, can contribute to clarify the question of the mechanisms that power the astrophysical accelerators which are known to exist from the observation of high-energy cosmic and gamma rays. Cosmic neutrinos can also be used to bring relevant information about the nature of dark matter, to study the intrinsic properties of neutrinos and to look for physics beyond the Standard Model. Likewise, atmospheric neutrinos can be used to study an ample variety of particle physics issues, such as neutrino oscillation phenomena, the determination of the neutrino mass ordering, non-standard neutrino interactions, neutrino decays and a diversity of other physics topics. In this article, we review a selected number of these topics, chosen on the basis of their scientific relevance and the involvement in their study of the Spanish physics community working in the KM3NeT and ANTARES neutrino telescopes.
Time calibration for the KM3NeT deep sea neutrino telescope Salesa-Greus, Francisco
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2011, Letnik:
626
Journal Article
Recenzirano
The KM3NeT Consortium aims to construct a deep sea research facility at the bottom of the Mediterranean Sea, which will house a neutrino detector of cubic kilometre scale. The detector will consist ...of a three-dimensional array of several thousands of photomultipliers, enabling the detection of muons induced by high energy cosmic neutrinos. In order to reach an angular resolution better than
0
.
1
∘
for energies above 100
TeV, high quality positioning and timing calibration are required. In this paper, the systems designed for the time calibration of the detector will be summarized, including their expected performances and some technical details.
Search for point-like sources with the ANTARES neutrino telescope Salesa-Greus, Francisco
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2011, Letnik:
630, Številka:
1
Journal Article
Recenzirano
The construction of the ANTARES neutrino telescope in the Mediterranean Sea next to the French coast of Toulon is completed since May 2008. The detector comprises about 900 photomultipliers ...distributed in 12 lines, at a depth of about 2500
m. Before its completion, the detector was operational with 5 out of the total 12 lines from February to December 2007. The data recorded in that period have been analysed. The search for point-like sources has been carried out using two strategies: a search within a list of several potential cosmic neutrino emitters and an all-sky scanning. The results obtained provide competitive limits for the Southern sky.
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